From d9f9b77d68c1e84261da480aa0f310e9a3bf70c3 Mon Sep 17 00:00:00 2001
From: Alexander Neumann <alexander@bumpern.de>
Date: Sun, 25 Oct 2015 15:28:01 +0100
Subject: [PATCH] Add Index.Packs() and IDSet.Equals()

---
 backend/idset.go         | 21 +++++++++++++++++++++
 repository/index.go      | 13 +++++++++++++
 repository/index_test.go | 15 +++++++++++++++
 3 files changed, 49 insertions(+)

diff --git a/backend/idset.go b/backend/idset.go
index 4f27f3489..817f80fff 100644
--- a/backend/idset.go
+++ b/backend/idset.go
@@ -39,6 +39,27 @@ func (s IDSet) List() IDs {
 	return list
 }
 
+// Equals returns true iff s equals other.
+func (s IDSet) Equals(other IDSet) bool {
+	if len(s) != len(other) {
+		return false
+	}
+
+	for id := range s {
+		if _, ok := other[id]; !ok {
+			return false
+		}
+	}
+
+	for id := range other {
+		if _, ok := s[id]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
 func (s IDSet) String() string {
 	str := s.List().String()
 	if len(str) < 2 {
diff --git a/repository/index.go b/repository/index.go
index b89d8f25e..66c734585 100644
--- a/repository/index.go
+++ b/repository/index.go
@@ -205,6 +205,19 @@ func (idx *Index) Each(done chan struct{}) <-chan PackedBlob {
 	return ch
 }
 
+// Packs returns all packs in this index
+func (idx *Index) Packs() backend.IDSet {
+	idx.m.Lock()
+	defer idx.m.Unlock()
+
+	packs := backend.NewIDSet()
+	for _, entry := range idx.pack {
+		packs.Insert(entry.packID)
+	}
+
+	return packs
+}
+
 // Count returns the number of blobs of type t in the index.
 func (idx *Index) Count(t pack.BlobType) (n uint) {
 	debug.Log("Index.Count", "counting blobs of type %v", t)
diff --git a/repository/index_test.go b/repository/index_test.go
index 75d69cd0b..331ce6a7f 100644
--- a/repository/index_test.go
+++ b/repository/index_test.go
@@ -325,3 +325,18 @@ func TestConvertIndex(t *testing.T) {
 		}
 	})
 }
+
+func TestIndexPacks(t *testing.T) {
+	idx := repository.NewIndex()
+	packs := backend.NewIDSet()
+
+	for i := 0; i < 20; i++ {
+		packID := randomID()
+		idx.Store(pack.Data, randomID(), packID, 0, 23)
+
+		packs.Insert(packID)
+	}
+
+	idxPacks := idx.Packs()
+	Assert(t, packs.Equals(idxPacks), "packs in index do not match packs added to index")
+}